Fighting cemetars with group style is easier than fighting them singly with strong style. It's risky, but less risky than focusing on one while others get to strike at you. Wyverns and royal wyverns are the same in this regard; there's a chance they'll get a knock-down and let everyone take a bite, but it's a smaller chance than if don't use group style.
Also, bloedzuigers can be fought with group style as long as careful attention is paid to their health levels, to cut the attack short and take evasive action as it dies. This effectively turns it into a landmine that will finish off the rest of the group for you.